多重敏感性共聚物的制备及其自组装行为研究

Synthesis of multistimuli-responsive polymer and its self-assembly behavior

采用开环聚合(ROP)和原子转移自由基聚合(ATRP)的方法合成了具有多重敏感性的聚乙二醇单甲醚-聚己内酯-聚甲基丙烯酸二乙氨基乙酯(mPEG-b-PCL-b-PDEAEMA)三嵌段共聚物,利用傅里叶变换红外光谱(FTIR)、核磁共振(NMR)和凝胶渗透色谱(GPC)对嵌段共聚物的结构及分子量进行了表征,改变投料比可有效调控各嵌段长度,所得共聚物的分子量分布均保持在1.3左右;其自组装后改变体系的pH、温度和CO2加入量可以有效控制聚集体的粒径大小,随CO2加入量的增加,粒径由238nm增大到538nm,而通入N2后其粒径大小恢复原状;对聚集体进行载药性能研究,发现CO2的加入可提高载药量及包封率,在释放阶段降低体系的pH或通入CO2可增加药物的释放速率和释放量。

In this paper, a novel multistimuli-responsive triblock copolymer poly （ ethyleneglycol ）-block-poly （ε-caprolactone ）-block-poly（ N,N-Diethylaminoethyl methacrylate） （ mPEG-PCL-PDEAEMA） was synthesized by ROP and ATRP. The structure and molecular weight of the triblock copolymer were characterized by flourier transform infrared（FTIR）,nuclear magnetic resonance （NMR）and gel permeation chromatography（GPC）. The length of chain segment could be controlled by changing feed ratio and the molecular weight distribution remained at 1. 3;After self-assemble,aggregates diameter could be controlled by pH,CO2 and tempera-ture. The diameter increased from 238nm to 538nm with increasing the amount of CO2 and could recover by purging with N2. The re-sults of drug loading property experiment showed that purging with CO2 can increase the drug loading and encapsulation efficiency, in the release stage,reduce the pH and purging with CO2 can increase drug release rate and release amount.